This invention is concerned with cigarette making machines of the type in which a cigarette filler stream is formed on a conveyor band which carries the filler stream, with the aid of suction, towards a rod forming section of the machine where the filler stream is enclosed in a continuous wrapper to form a continuous cigarette rod, this rod then being cut into sections of predetermined length. Before being fed into the rod forming section, the filler stream is normally trimmed by a trimming device acting on the filler stream while it is being compressed by a suctionally-induced air flow through the filler stream. In a common machine of this type, the filler stream is formed by tobacco showered through an upwardly extending channel onto the underneath surface of the band, and the filler stream is trimmed while being carried by the band.